Astronomers Discover Planet Made of Diamond

LONDON, Aug 25 (Reuters) - Astronomers have spotted an
exotic planet that seems to be made of diamond racing around a
tiny star in our galactic backyard.

The new planet is far denser than any other known so far and
consists largely of carbon. Because it is so dense, scientists
calculate the carbon must be crystalline, so a large part of
this strange world will effectively be diamond.

"The evolutionary history and amazing density of the planet
all suggest it is comprised of carbon -- i.e. a massive diamond
orbiting a neutron star every two hours in an orbit so tight it
would fit inside our own Sun," said Matthew Bailes of Swinburne
University of Technology in Melbourne.

Lying 4,000 light years away, or around an eighth of the way
towards the centre of the Milky Way from the Earth, the planet
is probably the remnant of a once-massive star that has lost its
outer layers to the so-called pulsar star it orbits.

Pulsars are tiny, dead neutron stars that are only around 20
kilometres (12.4 miles) in diameter and spin hundreds of times a
second, emitting beams of radiation.

In the case of pulsar J1719-1438, the beams regularly sweep
the Earth and have been monitored by telescopes in Australia,
Britain and Hawaii, allowing astronomers to detect modulations
due to the gravitational pull of its unseen companion planet.

The measurements suggest the planet, which orbits its star
every two hours and 10 minutes, has slightly more mass than
Jupiter but is 20 times as dense, Bailes and colleagues reported
in the journal Science on Thursday.

In addition to carbon, the new planet is also likely to
contain oxygen, which may be more prevalent at the surface and
is probably increasingly rare towards the carbon-rich centre.

Its high density suggests the lighter elements of hydrogen
and helium, which are the main constituents of gas giants like
Jupiter, are not present.

Just what this weird diamond world is actually like close
up, however, is a mystery.

"In terms of what it would look like, I don't know I could
even speculate," said Ben Stappers of the University of
Manchester. "I don't imagine that a picture of a very shiny
object is what we're looking at here."
(Reporting by Ben Hirschler; Editing by Sophie Hares)

By Ben Hirschler LONDON, Aug 25 (Reuters) - Astronomers have spotted an
exotic planet that seems to be made of diamond racing around a
tiny star in our galactic backyard. The new planet is far denser than any other known so far and
consists largely of carbon. Because...